1. Field of the Invention
The present invention relates to an apparatus and method for controlling an automatic ice machine for a refrigerator, and more particularly, to an apparatus and method for controlling an automatic ice machine, in which the ice-fullness detection of an ice box and the driving of the ice transfer motor can be performed, according to a detection signal generated from a photosensor.
2. Description of the Related Art
In general, in an automatic ice machine, a series of operations are repeatedly controlled such that water is supplied to an ice tray disposed in a freezer compartment, the ice tray is rotated downwardly by driving an ice transfer motor if freezing is sensed, the ice formed in the ice tray is transferred to an ice box disposed under the ice tray and is accumulated therein, and then an ice forming operation is performed again.
At an initial stage of the ice transfer operation, it is detected whether the ice box is full of ice to determine whether the ice transfer operation must be performed or not. If it is detected that the ice box is not full of ice, the ice transfer operation is performed. Here, the ice tray is rotated askew by the driving of the ice transfer motor so that the ice is transferred and then the ice tray is restored to its original position. The detection of ice-fullness of the ice box and the rotation operation of the ice transfer motor are controlled according to the detection results by each sensor.
The sensor is constituted by a switch operating mechanically. However, since the freezer compartment of the refrigerator is always in a low temperature and high humidity condition, the sensor may be frozen, and an error may be generated in forming or transferring ice, accordingly.
FIG. 1 is a schematic diagram of the above-described automatic ice machine for a refrigerator. The automatic ice machine comprises an ice vessel 120, an ice sensor 121 installed on the bottom surface of the ice vessel 120 for detecting the temperature of the ice vessel 120, a controller 110 having an ice transfer motor 111 for rotating the ice vessel 120 askew at a predetermined angle, a horizontaility sensing switch 115 for sensing the horizontality of the ice vessel 120, a polarity switch 112 for switching the rotation direction of the ice transfer motor 111 for restoring the ice vessel 120 positioned askew into its original position (horizontality) and an ice-fullness sensing switch 113 for sensing fullness of ice 131 accumulated in an ice box 130 by means of a sensing rod 114, a water tank sensing switch 143 for sensing, presence or absence of a water tank 140, a water storage chamber 142 for storing a predetermined amount of water in the water tank 140, and a pump motor 141 for pumping out water from the water storage chamber 142 to the ice vessel 120 through a water supply hose 150.
An ice transfer controlling method of the automatic ice machine having the aforementioned configuration will be described with reference to FIG. 2. Referring to FIG. 2, in step 201, it is determined whether freezing time of 2 or 3 hours is elapsed. If freezing time of 2 or 3 hours is elapsed, in step 202, it is determined whether freezing temperature is less than -9.degree. C. If freezing is detected by steps 201 and 202, the ice transfer motor 111 is driven to transfer ice to the ice box 130 (step 203).
Here, the ice vessel 120 is rotated in an ice transfer direction so that a latching portion (not shown) provided in the ice vessel 120 is latched by a latch (not shown) formed on a support structure (not shown) and is positioned askew at a predetermined angle to then be rotated, so that the ice generated in the ice vessel 120 falls down to the ice box 130 at a predetermined point, as shown in FIG. 1. Then, the polarity switch 112 is turned on so that the ice transfer motor 111 is rotated reversely and the ice vessel 120 is restored to its original position.
If the ice transfer operation is completed in the above-described manner, the controller 110 generates a control signal to the ice-fullness detection switch 113 to operate the sensing rod 114 for sensing whether the ice box 130 is full of the ice 131, and it is determined whether the ice box 130 is full of the ice 131 (step 204). If the ice-fullness state is detected, all operations are suspended until the ice-fullness state is resolved (step 205).
According to the conventional apparatus for controlling an automatic ice machine as the above, the polarity switch 112 for sensing a signal for controlling the rotation angle of the ice transfer motor 111 and the ice-fullness sensing switch 113 for sensing ice-fullness of the ice box 130 may be frozen, which results in malfunction. Also, the conventional apparatus for controlling an automatic ice machine requires many parts, which increases the manufacturing cost and makes the structure complex.